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A244929
Decimal expansion of Ti_2(2+sqrt(3)), where Ti_2 is the inverse tangent integral function.
2
2, 3, 3, 4, 5, 3, 7, 5, 8, 5, 3, 1, 2, 3, 4, 1, 1, 4, 6, 7, 5, 9, 0, 3, 8, 6, 2, 7, 7, 4, 3, 9, 3, 3, 0, 0, 4, 8, 8, 2, 6, 7, 8, 3, 7, 7, 2, 5, 0, 9, 9, 3, 5, 4, 0, 1, 6, 3, 0, 0, 5, 4, 0, 1, 8, 4, 4, 1, 8, 0, 1, 0, 3, 4, 5, 3, 6, 3, 3, 5, 0, 7, 6, 4, 5, 3, 6, 9, 0, 1, 6, 5, 4, 4, 1, 7, 1, 8, 3, 7, 9, 7, 1, 4, 4
OFFSET
1,1
REFERENCES
Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 1.7.6 Inverse Tangent Integral, p. 57.
LINKS
Eric Weisstein's MathWorld, Inverse Tangent Integral
Eric Weisstein's MathWorld, Polylogarithm
FORMULA
2/3*G + 5*Pi/12*log(2+Sqrt(3)), where G is Catalan's number.
Also equals i/2*(polylog(2, -i*(2+sqrt(3))) - polylog(2, i*(2+sqrt(3)))), with i = sqrt(-1).
EXAMPLE
2.3345375853123411467590386277439330048826783772509935401630054018441801...
MATHEMATICA
2/3*Catalan + 5*Pi/12*Log[2 + Sqrt[3]] // RealDigits[#, 10, 105]& // First
PROG
(PARI) default(realprecision, 100); 2/3*Catalan + 5*Pi/12*log(2 + sqrt(3)) \\ G. C. Greubel, Aug 25 2018
(Magma) SetDefaultRealField(RealField(100)); R:=RealField(); (2/3)*Catalan(R) + 5*Pi(R)*Log(2 + Sqrt(3))/12; // G. C. Greubel, Aug 25 2018
CROSSREFS
Sequence in context: A114544 A154726 A325784 * A302920 A280386 A204979
KEYWORD
cons,easy,nonn
AUTHOR
STATUS
approved